Mag primers in non-mag cartridges?

D.P.

Well-Known Member
Joined
May 21, 2004
Messages
225
Location
MD.
Any thoughts on using magnum primers in non-mag cartridges

I used them in a .257 Roberts with a slower powder and had excelent results. Nothing seemed to work until I tried this combo.
 
Mag primers can raise pressure in non-mag cases. No hard & fast rule, but working up loads over a chronograph will tell you the truth. Changing primers (different brands & mag & non-mag)can cause velocities and deviations to really change. Only the chrono knows! /ubbthreads/images/graemlins/blush.gif
 
i'm not an expert but my .02 .#1 mag are better in cold weather say 10f or below #2 using 60gr of powder or more.#3 hotter = higher pressure so careful at max load at std primer list.
 
Rimfire,
I have also used them alot for the "non-magnum" cartridges. I use them in my .22-250, .243, .260 and .25-06 right now. I usually try them after extensive load development with standard primers turn up nothing. Johnny K.
 
Other than cold weather performance, or a substantial quantity of hard to ignite ball powder, there is not much reason to use a mag primer, except for the thrill involved?

I think mag primers, in hot varmint cartridges are not recommended. If you accept the theory that capacity versus bore size will indicate a slow burning rate powder, then the mag primer defeats the purpose, and accelerates your burning rate, yielding slower velocity than a controlled burn with a large rifle primer.

In my 300Winchester, for example, I have always used W8½ primers and 80 grains of H4831, which produces a relatively hot spark (165) I could be wrong(?) but I think that Winchester uses that exact primer in loaded 300 Win Mag ammunition. And, yes, it is a hot large rifle primer. That tells me that Mag primers have a very narrow application. In other words, not a blanket solution. Unless you have a definite purpose, and understand the cause and effect.

Good hunting. LB
 
Absolute best accuracy I can get in my 223 match rounds is with mag small rifle primers. I don't use ball powder.

I work all my loads up from the bottom in all cartridges so pressure is not a concern. IE I won't swap a regular to a mag without backing down and starting over.

I have seen higher MV with match primers than with mag primers.

IMHO you cannot learn much from the label of primers(IE how hot per mag, reg or match etc....) And you simply have to use what works best. I've been able to double or triple group sizes with same powder by swapping primers. I've also cut group sizes in half or less by same tactic.

I test with every primer made at times. Just to see. I have loaded too long to get hung up to have to use a mag primer only in mags etc...

Jeff
 
Warning! This thread is more than 20 years ago old.
It's likely that no further discussion is required, in which case we recommend starting a new thread. If however you feel your response is required you can still do so.
Top